This invention relates to doors which are subject to operation in high winds and, more particularly, to a door stay that automatically locks the door in an open position when the door swings through a predetermined angle.
Specifications provided by customers often state that doors must remain open at a certain angle under all conditions. Conventional door stays, some of which are described below, are not suitable and could thus result in non-compliance with the customer specifications.
Current door stay designs that lock automatically after a predetermined movement of the door in the opening direction often rely on further door movement in the same direction to unlock the stay, allowing the door to close, for example, under a conventional biasing force in the closing direction. This is unsuitable in high wind areas where the door may unlatch inadvertently due to further movement of the door caused by the wind, and thus cause the door to close.
Conventional scissor-type automatic latching devices are also unsuitable for operation under high wind conditions where external forces are present.
There remains a need therefore, for a door stay that enables the door to automatically lock in the open position upon movement of the door through a predetermined angle, e.g. 80-130 degrees or more, but that will not unlatch due to unintended further movement of the door in either direction.